1. Field of the Invention
This invention relates generally to digital scan conversion techniques and more particularly to modular programmable digital scan converters responsive to a variety of types of sensor inputs.
2. Description of the Prior Art
The exploration of the problem of the display of data from a variety of sensors having different data rates and formats on a common indicator has resulted in the development over the past several years of a progression of multi-mode display systems ranging from dual-persistence cathode-ray tubes (CRT) to direct view storage tubes, analog scan converter tubes and digital scan conversion techniques. Numerous studies and applications have shown that a scan conversion function along with a high performance television compatible CRT display provides the best potential performance and flexibility. However, experience with analog scan conversion in field applications has demonstrated an inherent low reliability, poor performance and high cost of ownership. The reality of implementing a totally digital scan converter has awaited developments in digital technology, particularly in solid state memories and in MSI/LSI packaging density. Prior art digital scan converter/display systems have required an inordinate amount of development time, have been comparatively unreliable and have presented a high cost factor.
It would thus be a great advantage to the art to provide a digital scan converter system comprising basic building-block modules. It would also be a great advantage to the art to provide these basic modules in reduced volume and weight configurations. It would be a further advantage to the art to provide basic core modules from which various systems could be configured as required. Another advantage to the art would be realized by the implementation of a digital scan converter system operable under the control of micro-processor controllers. Changing of modes, parameters and growth achieved by reprogramming the memory of the controllers without necessitating any hardware changes would represent another significant advantage to the art. Achievement of readout in standard television raster format providing composite video interface and easy recording on video tape with superposition of symbology would represent an additional desirable advantage to the art.